The invention relates to a flexible surface electrode for carrying current to and from the skin of a human body and in the form of an insulated carrier which is covered with at least one electrically conductive foil which extends into a tongue projecting from the surface electrode, wherein the tongue is bent around a stiffening plate-like shaped portion in such a way that the electrically conductive foils face outwardly. The invention further relates to a plug connector for use with such a surface electrode.
With regard to surface electrodes as are used in particular as neutral electrodes in surgery, there is a wish for a connection, which can be made quickly but which is nonetheless secure, to the plug connector which is associated with the electrode. It has been found to be disadvantageous for the contact tongue of the surface electrode to be just as flexible as the electrode itself as it bends easily upon being inserted into a contact sleeve or upon being connected to a connecting clamp of the connector (DE-A-37 39 516).
DE-A-35 44 483 discloses a flexible surface electrode in which the conductive surface of the tongue is bent around an end edge of a shaped portion and thereby stiffened. However, contact with the tongue does not occur in the region of the end edge but in the end region of the tongue which extends parallel to the sleeve. In such arrangement, the conductive portion of the tongue is brought into force-locking contact by means of a spring-loaded pressure member with conductive layers provided on the wall of the sleeve. The spring-loaded pressure member quite considerably increases the structural height of the plug connector. In addition, the plug connector disclosed in DE-A-35 44 483 suffers from the disadvantage that the limit position of the tongue in the sleeve is not defined with sufficient degree of accuracy. Electrical contact still is made when the tongue is partially pulled out. That means that the conductive part of the surface of the tongue can come into contact directly with the skin of the patient. However, only a part of the electrode, the electrical resistance of which is substantially higher than that of the contact surfaces of the tongue is suitable for making contact with the skin.